Forging machine



Sept. 14 1926. 1,600,174

' A. T. HOLMAN ET AL FORGING MACHINE Filed April 4. 1925 H/L l i l 43 5555 i! |I|I .mgm's Patented Sept. 14, 1926.

ARTHUR TREVE HOLMAN, 0F CAMBORNE,

PATENT OFFICE.

AND KENNETH JAMES HOLMAN, 0F GARBIS BAY, ENGLAND, AS SIGNORS 'IO HOLMANBROTHERS LIMITED, OF CAMBORNE, ENG- LAND, A BRITISH COMPANY.

FORGING MACHINE.

Application filed April 4, 1925, Serial No. 20,714, and 111 GreatBritain -.Tanuary 13, 19 25.

This invention relates to forging machines, and particularly to animproved valve mechanism for sequentially operating the work holding andforging mechanisms. The invention is herein described and shown asapplied to the type of forging machine shownin British specification No.5452/1924.

In machines of the type to which the present invention relates a pair ofjaws or other work-holding members 1s provided, one of which jaws ormembers is movable by means of a piston-and-cylinder device towards theother. The jaws are adapted to hold between them the drill bit or thelike while a reciprocating dollyor forging hammer operates on the endface of the bit or the like.

With such jaws there is'also generally and preferably associated a partWhlCh serves to forge or shape portions of the drill bit before endsharpening orshaping is effected by the dolly. v

The forging machine to which the present invention is shown herein asapplied comprises the combination of a movable jaw with two pistonsand-cylinders arranged 1n tandem, the pistons being both carried onasingle piston rod and serving jointly,when the dollyis to be used, toactuate the movable jaw'to close it on toor towards the companion jaw. Ir

According to'the present invention in 'or for a forging machine havingthe characteristic features above referred'to, control means is providedfor supplying driving fluid at will eithe'rj (at) To one'cylinder'alone(for example the' uppercylinder) 1 p Y Y (b) To both cylinderssimultaneously; or (0) To bot-h cylinders and to the cylinder of thedolly hammer simultaneously,

When the two pistons abovere ferred to are associated with a thirdpiston and cylinder constituting the meansv for, returning the *movablejaw tothe open position, the present invention further comprises thecombi nation of a chamber to which driving-fiuid;

is supplied, a conduit which'isalways; in 0 en communication therewithand" with the cylinder of the'thlrd or return p ston,

and another conduit whichfislopen atoneend to the said chamber andfiatthe other and leads to the control means above stated.

E sels/the sweetie-whees r s,

fluid is supplied is provided'by or support for the machine,

In order that the inventlon may be more. clearly understood, onepreferred construca pedestal tion will now be described with referenceto the accompanying drawing whi'chillustrates a central. sectionalelevation of the machine in a plane transverse to that containing theaxis of the dolly hammer.

The machine now illustrated is similar pistons are all mounted. on a;single piston rod 15. The two pistons 13 and114 serve when'requiredjointly to move the movable jaw, which is formed on or appliedtol thelower face of the upper piston 14, towards the fixed jaw constitutedbyor mounted vin the head of the cylinderllr The piston 31 serves as areturn piston for opening the movable jaw.

These parts have: been given" the same reference numerals as were givenin the prior specification and are in all their essentials similar inconstruction to those previously described.

The control means for the air supply; to the several cylindersis in thepresent inventiouas follows :--The pedestal 10 is formed as a hollowchamber into; which compressed airorother motive fluid .isladmittedthrough an orifice 40. This orifice is screw-threaded so; as to receiveascrewed I union vofia hose or other conduit through which thedriving'fluid is conducted to the machine. In the lower end of thecylinder 32 there is an aperture 41 byr'which the cylinder 32 ismaintained alwaysin-open jchamoer in the pedestal 10. 5

.Anoutlet -conduit r42 from the chamber leads through a port 43 iintothe cylinder 44 of a reciprocating piston controlvalve 45.

communication with the interior of'the air which make a substantiallyair tight sliding .fit'in the cylinder 44;

the cylinder 12 communicates with the valve The latter comprises:valvewstem having .two enlargedcylindricalport ions46 and 47 A conduit48 leading to the upper endof' cylinder 44 through a port 49 andaconduit 50 leading tot-he upper end of the lower cylinder 11 alsocommunicates with the valve cylinder t lthrough a port 51. j I

.A'nother port 52 opening intothe cylinder 445 communicates with ascrew-threaded orilice 53 adapted to receive a hose orother conduitconnect-ion leading to the cylinder 61 of the dolly hammer 62.

There is also a port opening into the cylinder 14 and communicating withan exhaust orificeee.

The end of the. valve s indle is formed as a rack which is engaged y atoothed segment -56 mounted on a rock shaft 57 which can be rockedaboutrits axis by means of a handle 58.

- It will be seen therefore that by movement 'of'the handle 58 the valve45 can be moved to three control positions. In the position illustratedmotive fluid is admitted through the conduit 42 and ports 13 and 19 tothe conduit 18 and thence to the upper end of the cylinder 12. This willhave the effect of moving the movable jaw down wardly onto the fiXGCljaw to impart a sharp blow to the bit or other work to be operated upon.During the admission of motive fluid to the'piston 12, that is to say inthe position of the valve illustrated, the exhaust port 54: is closedoff from the conduit 48 but isopen'ed to the'cylinder '61 "of the dollyhammer 62 through the port 52. Also the conduit 5 1 communicating withthe lower cylinder '11 is "closed. By moving the bandle 58 in such amanner as to return the valve towards the left to the end or its strokethe air admission port 43 will be closed-and the port 49' will be openedto the exhaust port 51. The driving fluid is thereby released from thecylinder 12 and the return piston 31 then operates to raise the upperpiston 14. Thus by rocking the control-handle 58 backwards and forwards-'betiveen the two positionsjust'described the upper piston 14 ormovable jaw can be reciprocate'das rapidly as desired to impart a(succession o'f'blows to the work *which is positioned in the lowerfixed jaw. I

when it is required to operate on the end face oft-he work'by mea'nsofthe dolly hammer '62, it is found desirable to hold the :movable jawonto the work with'a relative sly great pressure, and for this purpose thecontrol handle is movedso'that the enlarg'ed 43 thereby setting portion16 of the valve 45 -opens not only 1 the poi-r 4.9but also the port 51"to the -ad mission port 13. Consequently "driving fluid is admitted toboth-ofthe cylinders 11 and It will be seenjthereifore that byineans ofthe control handle 58 the forging hammer or movable jaw piston can bereciprocatedto impart a succession of blows to the work by alternatelyadmitting driving fluid to, and releasing it from, the upper cylinder12.

Al-ternatively for heavier blows the handle can be rocked through agreater angle so as to admit the driving'fluid to both cylinders 11 and12 simultaneously. It will be further seen that the dolly Fhammer 62 isnot, and cannot be, energized until driving fluid is admitted to bothcylinders 11 and '12 whereby. the work is gripped between the jaws withthe "required pressure.

As a 'detail of construction it will be seen 7 that at the lower 'end'ofthe pedestal 1C there is a removable inspection cover by the removal-ofwhich access is obtalned to the interior of the chamber in the :ped- JAlthough 'a particular form of apparatus embodying the present inventionhas been described in detail, it is obvious that many modifications may,be made in the construcand cylinders arranged in tandem, which'pis'tons'are both connected. to said pistonrod and serve omtly to movesaid movable .jaw towards the companion jaw, a driving fluid supplyconduit, three delivery condu ts whereoifzone opens into-one, the secondopens into the other 01"? said cylindersandthe third is forco'nnectionto the cylinder o'f'a reciprocating forging hammer arranged to -op"erate :on the work while it is held by said jaws, and-control meansforcontrolling the supply of driving-fluid from said supply "conduit atwill eitherto oneo-f the-twoffi-rstmentioned delivery conduits alone,"or. to

both of the same simultaneously, or to all three said ideliveryconduitssimultaneously.

2. Atorging-machine-of'the character de scribed, comprisingincombination two opposed work-holding jaws, one at least of ,whichismovable relatively towards and.

,away from the other, a single piston-rod connected with the movablejaw, two pistons and cylinders arranged in tandem, which pistons 'a-rebothconnected tosaid fpis t'on-rod and serve jointly to move saidmovablejjaw towards thecompanion, jaw, a

V driving-fluid supply conduit, three delivery conduits whereof oneopens into one, the.

second opensinto rtlieiotherof said cylinders ,and' thethird is for.connectionto thei'Cylv inder of a reciprocatory forging-hammer 1 3%ranged to operate on the work while it is held by said jaws, athree-position reciprocating valve for controlling the Supply ofdriving-fluid from said supply conduit at will either to one of the twofirst mentioned delivery-conduits alone or to both of the samesimultaneously, or to all three said delivery-conduits simultaneously,and arackand-pinion device for operating said valve.

3. A forging machine of the character described, comprising incombination two opposed worlcholding jaws, one at least of which ismovable relatively towards and away from the other, a single piston-rodconnected with the movable jaw, two pistons and cylinders arranged intandem, which pistons are both connected to said piston-rod and servejointly to move said movable jaw towards the companion jaw, a chamber towhich driving-fluid can be supplied, which chamber constitutes apedestal for supporting the machine, a third cylinder always in opencommunication with said chamber, a third piston earned by said plstonrodand movable in the said third cylinder, a driving-fluid supply conduitwhich opens at one end into said chamber, three delivery-conduitswhereof one opens into one and the other opens into the other of the twofirst mentioned cylinders, and the third is for connection to thecylinder of a reciprocatory forging hammer arranged to operate on thework while it is held by said jaws, a three-position reciprocatingpistonvalve having a stem constituting a toothed rack for controllingthe supply of drivingfiuid'from the other end of said supply-conduit atwill either to one of the two firstmentioned delivery-conduits alone, orto both of the same simultaneously, or to all three saiddelivery-conduitssimultaneously, a toothed segment meshing with saidrack, and a handle for oscillating said segment.

4. A forging machine of the character described, comprising incombination two opposed Work-holding jaws, one at least of which ismovable relatively towards; and

driving-fluid from said conduit at will either to one of the two firstmentioned delivery conduits alone, or to both of the same simultaneouslyor to all three said delivery conduits simultaneously, and forconnecting one of the first-mentioned delivery conduits first to saidsupply conduit whilst shutting it OK from the exhaust port and then tosaid exhaust port whilst shutting it off from the supply conduit forreciprocating said piston-rod.

In testimonywhereof we have signed our names to this specification.

ARTHUR TREVE HOLMAN.

KENNETH JAMES HOLMAN.

